Piston king



f Patna Jan. 15, 1929.

. cylinder.

D T T TiES PATE Nr o PIsTo N RING.

l i :"h I App a filed ptember 13, 1925.8eria1 No. 57,291. R weamvempu 23, 1928.

My invention-relates to improvements in piston rings and the object of the invention is to devise' fan'improved pistonring. particu larly suitable for use'in internal combustion 4 engines whereby a more perfect operation may be obtained. and whereby a snug and proper fit ofthe' ring in the ring groove and against the cylinder is assured, thus more cffectively preventing leaka e past the ring; a further object is to provi e a ring which not likely to become jammed or wedged within the cylinder thus eliminating the re sulting-lmocking and other troubles.

Further objects will appear in the course of the lfollowing specification;

My invention consists in the construction and arrangement of parts, all as hereinafter more particularly described and illustrated in. the accompanying drawings in which zo Figwl is an enlarged longitudinal fragmentary section of aportion of a cylinder fitte the ring being shown in its original form when'initially installed and before any wear has occurred.

" 3o cylinder and piston therein, with my improved ring fitted, the section being taken on the line-3 3'o Fig. 2.

In the drawings, like characters of reference indicate corresponding parts in the we rious views. v

My invention is applicable to any ordinary piston. 1 having a circumferential ring groove'2 and mounted within a cylinder 3.

My improved ring comprises an inner ring 40 section 4 and an outer ring section 5.

Each of these ring sections is narrower than the ring groove 2 and. are of smaller diameter than the cylinder 3 so that normally the ring would slide loosely through the The ring sections are also made soft'so that of themselves they have no resilient engagement against the cylinder wall.

The ring sections are formed with meeting faces 6 "and 71inclined at fifty degrees obliquely to the axis of the rim".

The "oblique face 6 of the outer ring section 5 terminates at its bottom edge in a straight portion '8 disposed parallel to the plane of the ring and the oblique face 7 of andfiston therein Withmy improved ring the inner. ring-section ,4 terminates at its bottom edge .in a straight portion 9*alsof.

disposed parallel to the plane of thering.

T he portion 9 of the inner section. 4 p'roccts beyond the outer face of the outcr scction 5 and the under' edge of the inner sec- -tion is inclined away from the edge of this 'outer face of the outer scction,,the purfiosc of which will'prescntly be explained.

A fiat spring 12' is mou'nterlwithin thering 1 groove 2 behind the inner ring section 4. y y

This spring is o'f'pcculia'r shape having 701 five long sides -and-fiveshort sides alter-Q nating between the long sides- Due to this form, otthe spring, it heal-s5 against the piston at five points 13 and against the inner ring: section. at -1O points 14, so that the ring will'work 'upon the piston instead of upon the ring and will not wear through on the outer corners.

When my ring is initially installed, the outer ring section 5 is superimposed upon the 8 inncr'ring section 4 and the springlil will the normal diameter of the'outer section 5 is less "than that of the cylinder, whenthus initially installed this outer section simply' rests loosely upon the inclined face of the inner section but does not contact with the cylinder wall (see Fig. 1). i lVhen initially installed the only portion of the entire ring which engages-the cylinder wall is the thin circumferential'ridge 11.

As a matter of fact when initially installed the outer section 5 lies quite loosely in the 95. groove and is not pressed into engagement with either the wall of the ring groove or with the cylinder wall. I r i From' the above it will be evident that when initially installed the outer section 5 v is quite loose and when the engine is first run the oil may, freely work up and around the' ring sections] 1 As running continues the thin circumferential ridge 11 soon wears and this wear is immediately compensated for by the spring 12 expanding the inner ring section 4 and maintaining it pressed against the cylinder Wall.

As this wear continues,.with the resultant amass- Y j smn'oniinaxannnn BOWMAN, or s'r. LOUISLMIUSSIQURL'QZ expansion of the inner ring section 4, the outer section 5 is expanded thereby that the ring'as a whole expands laterall to properly fill the ring groove-and radial y so B-that the outer faceofthe outer section *5 is pressed against the cylinder wal-l (see Fig. 2). o

Thus as soon as the initial wear has taken place, the ring is expanded both laterally ll) and radially to eiie'ctively and fully fill-the Y ring groove and the outer ring section' is pressed tightly against the cylinder wall to prevent any leakage past the ring.

Aswear continues the ring' will continue to automatically expand as required to compensate for all wear.

By the construction whereby the ring seetions are normally ofless diameter than the cylinder and whereby, when initially installed the outer section is quite loose in the ring groove and cylinder, the operation of fitting the piston into the cylinder is greatly facilitated.

Serious trouble is experienced in two piece piston 'rings'due to the outer section being forced down over the inner section thus causing the sections to jam 01' wedge in the cylinder, resulting in knocking and -other troubles. 1

# In .my improved ring this has been entirely overcome b the provision of the portions 8 and 9 which portions when the ring is installed are in juxtaposition and form opposed shoulders which come into engagement .should the sections tend H axially past each other; j i y 1 By this means the extent ito'whi h" outer section canslide over the tion is positively limited and jammin Wedging of the ring in the cylinder is positively prevented.

From the foregoing it will, beevident-tliat I have devised valuable improvements-in Piston ngs whereby the ob ects of vention have been attained,- I

\Vhat I claim as my. invention is: i;

piston therein having a'eircumferential rin groove, of a piston ring in said groove, sai ring compr sing two superlm osed r1ng= sec-.1,

tions, the normal diameter 0 said rin sections being smaller than that of the cylinder The combination with a cylinder bind? a}. i

bore and each section being narrower than the ring groove, a spring mounted within: v the groove behind the piston ring. and eib" panding the ring outwardly, the meet' faces of the ring sections being formed wit corresponding portions inclined obliquely to the axis of the rim, said inclined portions terminating at the'bottom in juxtaposedportions parallel to the lane of the' T siMnon ALEXANDER BOWMAN.) 

